diff --git a/PNChart/PNBarChart/PNBar.m b/PNChart/PNBarChart/PNBar.m
index c6a61505..f92b6553 100644
--- a/PNChart/PNBarChart/PNBar.m
+++ b/PNChart/PNBarChart/PNBar.m
@@ -59,8 +59,8 @@ - (void)setGrade:(float)grade
     CABasicAnimation *pathAnimation = [CABasicAnimation animationWithKeyPath:@"strokeEnd"];
     pathAnimation.duration = 1.0;
     pathAnimation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
-    pathAnimation.fromValue = [NSNumber numberWithFloat:0.0f];
-    pathAnimation.toValue = [NSNumber numberWithFloat:1.0f];
+    pathAnimation.fromValue = @0.0f;
+    pathAnimation.toValue = @1.0f;
     [_chartLine addAnimation:pathAnimation forKey:@"strokeEndAnimation"];
 
     _chartLine.strokeEnd = 1.0;
diff --git a/PNChart/PNBarChart/PNBarChart.m b/PNChart/PNBarChart/PNBarChart.m
index 90b5566b..7d626604 100644
--- a/PNChart/PNBarChart/PNBarChart.m
+++ b/PNChart/PNBarChart/PNBarChart.m
@@ -244,8 +244,8 @@ - (void)strokeChart
         CABasicAnimation *pathAnimation = [CABasicAnimation animationWithKeyPath:@"strokeEnd"];
         pathAnimation.duration = 0.5;
         pathAnimation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
-        pathAnimation.fromValue = [NSNumber numberWithFloat:0.0f];
-        pathAnimation.toValue = [NSNumber numberWithFloat:1.0f];
+        pathAnimation.fromValue = @0.0f;
+        pathAnimation.toValue = @1.0f;
         [_chartBottomLine addAnimation:pathAnimation forKey:@"strokeEndAnimation"];
         
         _chartBottomLine.strokeEnd = 1.0;
@@ -276,8 +276,8 @@ - (void)strokeChart
         CABasicAnimation *pathLeftAnimation = [CABasicAnimation animationWithKeyPath:@"strokeEnd"];
         pathLeftAnimation.duration = 0.5;
         pathLeftAnimation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
-        pathLeftAnimation.fromValue = [NSNumber numberWithFloat:0.0f];
-        pathLeftAnimation.toValue = [NSNumber numberWithFloat:1.0f];
+        pathLeftAnimation.fromValue = @0.0f;
+        pathLeftAnimation.toValue = @1.0f;
         [_chartLeftLine addAnimation:pathLeftAnimation forKey:@"strokeEndAnimation"];
         
         _chartLeftLine.strokeEnd = 1.0;
diff --git a/PNChart/PNCircleChart/PNCircleChart.m b/PNChart/PNCircleChart/PNCircleChart.m
index b2310e4a..d9f59f72 100644
--- a/PNChart/PNCircleChart/PNCircleChart.m
+++ b/PNChart/PNCircleChart/PNCircleChart.m
@@ -40,7 +40,7 @@ - (id)initWithFrame:(CGRect)frame andTotal:(NSNumber *)total andCurrent:(NSNumbe
         CGFloat startAngle = clockwise ? -90.0f : 270.0f;
         CGFloat endAngle = clockwise ? -90.01f : 270.01f;
 
-        _lineWidth = [NSNumber numberWithFloat:8.0];
+        _lineWidth = @8.0f;
         UIBezierPath *circlePath = [UIBezierPath bezierPathWithArcCenter:CGPointMake(self.center.x, self.center.y) radius:self.frame.size.height * 0.5 startAngle:DEGREES_TO_RADIANS(startAngle) endAngle:DEGREES_TO_RADIANS(endAngle) clockwise:clockwise];
 
         _circle               = [CAShapeLayer layer];
@@ -94,8 +94,8 @@ - (void)strokeChart
     CABasicAnimation *pathAnimation = [CABasicAnimation animationWithKeyPath:@"strokeEnd"];
     pathAnimation.duration = 1.0;
     pathAnimation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
-    pathAnimation.fromValue = [NSNumber numberWithFloat:0.0f];
-    pathAnimation.toValue = [NSNumber numberWithFloat:[_current floatValue] / [_total floatValue]];
+    pathAnimation.fromValue = @0.0f;
+    pathAnimation.toValue = @([_current floatValue] / [_total floatValue]);
     [_circle addAnimation:pathAnimation forKey:@"strokeEndAnimation"];
     _circle.strokeEnd   = [_current floatValue] / [_total floatValue];
 
diff --git a/PNChart/PNLineChart/PNLineChart.m b/PNChart/PNLineChart/PNLineChart.m
index 06942d21..1772c959 100644
--- a/PNChart/PNLineChart/PNLineChart.m
+++ b/PNChart/PNLineChart/PNLineChart.m
@@ -238,8 +238,8 @@ - (void)strokeChart
         CABasicAnimation *pathAnimation = [CABasicAnimation animationWithKeyPath:@"strokeEnd"];
         pathAnimation.duration = 1.0;
         pathAnimation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
-        pathAnimation.fromValue = [NSNumber numberWithFloat:0.0f];
-        pathAnimation.toValue = [NSNumber numberWithFloat:1.0f];
+        pathAnimation.fromValue = @0.0f;
+        pathAnimation.toValue = @1.0f;
         [chartLine addAnimation:pathAnimation forKey:@"strokeEndAnimation"];
 
         chartLine.strokeEnd = 1.0;
diff --git a/PNChartDemo/PCChartsTableViewController.m b/PNChartDemo/PCChartsTableViewController.m
index af46b486..1521dc58 100644
--- a/PNChartDemo/PCChartsTableViewController.m
+++ b/PNChartDemo/PCChartsTableViewController.m
@@ -70,7 +70,7 @@ - (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
         data01.color = PNFreshGreen;
         data01.itemCount = lineChart.xLabels.count;
         data01.getData = ^(NSUInteger index) {
-            CGFloat yValue = [[data01Array objectAtIndex:index] floatValue];
+            CGFloat yValue = [data01Array[index] floatValue];
             return [PNLineChartDataItem dataItemWithY:yValue];
         };
 
@@ -80,7 +80,7 @@ - (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
         data02.color = PNTwitterColor;
         data02.itemCount = lineChart.xLabels.count;
         data02.getData = ^(NSUInteger index) {
-            CGFloat yValue = [[data02Array objectAtIndex:index] floatValue];
+            CGFloat yValue = [data02Array[index] floatValue];
             return [PNLineChartDataItem dataItemWithY:yValue];
         };
 
@@ -135,7 +135,7 @@ - (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
         circleChartLabel.font = [UIFont fontWithName:@"Avenir-Medium" size:23.0];
         circleChartLabel.textAlignment = NSTextAlignmentCenter;
         
-        PNCircleChart * circleChart = [[PNCircleChart alloc] initWithFrame:CGRectMake(0, 80.0, SCREEN_WIDTH, 100.0) andTotal:[NSNumber numberWithInt:100] andCurrent:[NSNumber numberWithInt:60] andClockwise:YES andShadow:YES];
+        PNCircleChart * circleChart = [[PNCircleChart alloc] initWithFrame:CGRectMake(0, 80.0, SCREEN_WIDTH, 100.0) andTotal:@100 andCurrent:@60 andClockwise:YES andShadow:YES];
         circleChart.backgroundColor = [UIColor clearColor];
         [circleChart setStrokeColor:PNGreen];
         [circleChart strokeChart];
diff --git a/README.md b/README.md
index 42b9d720..c2d07eaa 100644
--- a/README.md
+++ b/README.md
@@ -49,7 +49,7 @@ You will need LLVM 3.0 or later in order to build PNChart.
   data01.color = PNFreshGreen;
   data01.itemCount = lineChart.xLabels.count;
   data01.getData = ^(NSUInteger index) {
-      CGFloat yValue = [[data01Array objectAtIndex:index] floatValue];
+      CGFloat yValue = [data01Array[index] floatValue];
       return [PNLineChartDataItem dataItemWithY:yValue];
   };
   // Line Chart No.2
@@ -58,7 +58,7 @@ You will need LLVM 3.0 or later in order to build PNChart.
   data02.color = PNTwitterColor;
   data02.itemCount = lineChart.xLabels.count;
   data02.getData = ^(NSUInteger index) {
-      CGFloat yValue = [[data02Array objectAtIndex:index] floatValue];
+      CGFloat yValue = [data02Array[index] floatValue];
       return [PNLineChartDataItem dataItemWithY:yValue];
   };